Wine Cross Reference
wine/dlls/riched20/caret.c

   /*
    * RichEdit - Caret and selection functions.
    *
    * Copyright 2004 by Krzysztof Foltman
    * Copyright 2005 by Phil Krylov
    *
    * This library is free software; you can redistribute it and/or
    * modify it under the terms of the GNU Lesser General Public
    * License as published by the Free Software Foundation; either
   * version 2.1 of the License, or (at your option) any later version.
   *
   * This library is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   * Lesser General Public License for more details.
   *
   * You should have received a copy of the GNU Lesser General Public
   * License along with this library; if not, write to the Free Software
   * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
   */
  
  
  #include "editor.h"
  
  WINE_DEFAULT_DEBUG_CHANNEL(richedit);
  
  static BOOL
  ME_MoveCursorChars(ME_TextEditor *editor, ME_Cursor *pCursor, int nRelOfs);
  
  void ME_GetSelection(ME_TextEditor *editor, int *from, int *to)
  {
    *from = ME_GetCursorOfs(editor, 0);
    *to =   ME_GetCursorOfs(editor, 1);
    
    if (*from > *to)
    {
      int tmp = *from;
      *from = *to;
      *to = tmp;    
    }
  }
  
  int ME_GetTextLength(ME_TextEditor *editor)
  {
    return ME_CharOfsFromRunOfs(editor, ME_FindItemBack(editor->pBuffer->pLast, diRun), 0);   
  }
  
  
  int ME_GetTextLengthEx(ME_TextEditor *editor, const GETTEXTLENGTHEX *how)
  {
    int length;
  
    if (how->flags & GTL_PRECISE && how->flags & GTL_CLOSE)
      return E_INVALIDARG;
    if (how->flags & GTL_NUMCHARS && how->flags & GTL_NUMBYTES)
      return E_INVALIDARG;
    
    length = ME_GetTextLength(editor);
  
    if ((GetWindowLongW(editor->hWnd, GWL_STYLE) & ES_MULTILINE)
          && (how->flags & GTL_USECRLF)
          && !editor->bEmulateVersion10) /* Ignore GTL_USECRLF flag in 1.0 emulation */
      length += editor->nParagraphs - 1;
    
    if (how->flags & GTL_NUMBYTES)
    {
      CPINFO cpinfo;
      
      if (how->codepage == 1200)
        return length * 2;
      if (how->flags & GTL_PRECISE)
        FIXME("GTL_PRECISE flag unsupported. Using GTL_CLOSE\n");
      if (GetCPInfo(how->codepage, &cpinfo))
        return length * cpinfo.MaxCharSize;
      ERR("Invalid codepage %u\n", how->codepage);
      return E_INVALIDARG;
    }
    return length; 
  }
  
  
  int ME_SetSelection(ME_TextEditor *editor, int from, int to)
  {
    int selectionEnd = 0;
    const int len = ME_GetTextLength(editor);
  
    /* all negative values are effectively the same */
    if (from < 0)
      from = -1;
    if (to < 0)
      to = -1;
  
    /* select all */
    if (from == 0 && to == -1)
    {
      editor->pCursors[1].pRun = ME_FindItemFwd(editor->pBuffer->pFirst, diRun);
      editor->pCursors[1].nOffset = 0; 
      editor->pCursors[0].pRun = ME_FindItemBack(editor->pBuffer->pLast, diRun); 
      editor->pCursors[0].nOffset = 0;
     ME_InvalidateSelection(editor);
     ME_ClearTempStyle(editor);
     return len + 1;
   }
 
   /* if both values are equal and also out of bound, that means to */
   /* put the selection at the end of the text */
   if ((from == to) && (to < 0 || to > len))
   {
     selectionEnd = 1;
   }
   else
   {
     /* if from is negative and to is positive then selection is */
     /* deselected and caret moved to end of the current selection */
     if (from < 0)
     {
       int start, end;
       ME_GetSelection(editor, &start, &end);
       editor->pCursors[1] = editor->pCursors[0];
       ME_Repaint(editor);
       ME_ClearTempStyle(editor);
       return end;
     }
 
     /* adjust to if it's a negative value */
     if (to < 0)
       to = len + 1;
 
     /* flip from and to if they are reversed */
     if (from>to)
     {
       int tmp = from;
       from = to;
       to = tmp;
     }
 
     /* after fiddling with the values, we find from > len && to > len */
     if (from > len)
       selectionEnd = 1;
     /* special case with to too big */
     else if (to > len)
       to = len + 1;
   }
 
   if (selectionEnd)
   {
     editor->pCursors[1].pRun = editor->pCursors[0].pRun = ME_FindItemBack(editor->pBuffer->pLast, diRun);
     editor->pCursors[1].nOffset = editor->pCursors[0].nOffset = 0;
     ME_InvalidateSelection(editor);
     ME_ClearTempStyle(editor);
     return len;
   }
 
   ME_RunOfsFromCharOfs(editor, from, &editor->pCursors[1].pRun, &editor->pCursors[1].nOffset);
   ME_RunOfsFromCharOfs(editor, to, &editor->pCursors[0].pRun, &editor->pCursors[0].nOffset);
   return to;
 }
 
 
 void
 ME_GetCursorCoordinates(ME_TextEditor *editor, ME_Cursor *pCursor,
                         int *x, int *y, int *height)
 {
   ME_DisplayItem *pCursorRun = pCursor->pRun;
   ME_DisplayItem *pSizeRun = pCursor->pRun;
 
   assert(height && x && y);
   assert(!(ME_GetParagraph(pCursorRun)->member.para.nFlags & MEPF_REWRAP));
   assert(pCursor->pRun);
   assert(pCursor->pRun->type == diRun);
   
   if (pCursorRun->type == diRun) {
     ME_DisplayItem *row = ME_FindItemBack(pCursorRun, diStartRowOrParagraph);
 
     if (row) {
       HDC hDC = GetDC(editor->hWnd);
       ME_Context c;
       ME_DisplayItem *run = pCursorRun;
       ME_DisplayItem *para = NULL;
       SIZE sz = {0, 0};
     
       ME_InitContext(&c, editor, hDC);
       
       if (!pCursor->nOffset)
       {
         ME_DisplayItem *prev = ME_FindItemBack(pCursorRun, diRunOrParagraph);
         assert(prev);
         if (prev->type == diRun)
           pSizeRun = prev;
       }
       assert(row->type == diStartRow); /* paragraph -> run without start row ?*/
       para = ME_FindItemBack(row, diParagraph);
       assert(para);
       assert(para->type == diParagraph);
       if (editor->bCaretAtEnd && !pCursor->nOffset && 
           run == ME_FindItemFwd(row, diRun))
       {
         ME_DisplayItem *tmp = ME_FindItemBack(row, diRunOrParagraph);
         assert(tmp);
         if (tmp->type == diRun)
         {
           row = ME_FindItemBack(tmp, diStartRow);
           pSizeRun = run = tmp;
           assert(run);
           assert(run->type == diRun);
           sz = ME_GetRunSize(&c, &para->member.para,
                              &run->member.run, ME_StrLen(run->member.run.strText),
                              row->member.row.nLMargin);
         }
       }
       if (pCursor->nOffset) {
         sz = ME_GetRunSize(&c, &para->member.para, &run->member.run, pCursor->nOffset,
                            row->member.row.nLMargin);
       }
 
       *height = pSizeRun->member.run.nAscent + pSizeRun->member.run.nDescent;
       *x = run->member.run.pt.x + sz.cx;
       *y = para->member.para.nYPos + row->member.row.nBaseline + run->member.run.pt.y - pSizeRun->member.run.nAscent - ME_GetYScrollPos(editor);
       ME_DestroyContext(&c, editor->hWnd);
       return;
     }
   }
   *height = 10; /* FIXME use global font */
   *x = 0;
   *y = 0;
 }
 
 
 void
 ME_MoveCaret(ME_TextEditor *editor)
 {
   int x, y, height;
 
   if (ME_WrapMarkedParagraphs(editor))
     ME_UpdateScrollBar(editor);
   ME_GetCursorCoordinates(editor, &editor->pCursors[0], &x, &y, &height);
   if(editor->bHaveFocus)
   {
     RECT rect;
 
     GetClientRect(editor->hWnd, &rect);
     x = min(x, rect.right-2);
     CreateCaret(editor->hWnd, NULL, 0, height);
     SetCaretPos(x, y);
   }
 }
 
 
 void ME_ShowCaret(ME_TextEditor *ed)
 {
   ME_MoveCaret(ed);
   if(ed->bHaveFocus)
     ShowCaret(ed->hWnd);
 }
 
 void ME_HideCaret(ME_TextEditor *ed)
 {
   if(ed->bHaveFocus)
   {
     HideCaret(ed->hWnd);
     DestroyCaret();
   }
 }
 
 void ME_InternalDeleteText(ME_TextEditor *editor, int nOfs, 
   int nChars)
 {
   ME_Cursor c;
   int shift = 0;
   
   while(nChars > 0)
   {
     ME_Run *run;
     ME_CursorFromCharOfs(editor, nOfs, &c);
     run = &c.pRun->member.run;
     if (run->nFlags & MERF_ENDPARA) {
       int eollen = run->nCR + run->nLF;
 
       if (!ME_FindItemFwd(c.pRun, diParagraph))
       {
         return;
       }
       ME_JoinParagraphs(editor, ME_GetParagraph(c.pRun));
       /* ME_SkipAndPropagateCharOffset(p->pRun, shift); */
       ME_CheckCharOffsets(editor);
       nChars -= (eollen < nChars) ? eollen : nChars;
       continue;
     }
     else
     {
       ME_Cursor cursor;
       int nIntendedChars = nChars;
       int nCharsToDelete = nChars;
       int i;
       int loc = c.nOffset;
       
       ME_FindItemBack(c.pRun, diParagraph)->member.para.nFlags |= MEPF_REWRAP;
       
       cursor = c;
       ME_StrRelPos(run->strText, loc, &nChars);
       /* nChars is the number of characters that should be deleted from the
          FOLLOWING runs (these AFTER cursor.pRun)
          nCharsToDelete is a number of chars to delete from THIS run */
       nCharsToDelete -= nChars;
       shift -= nCharsToDelete;
       TRACE("Deleting %d (intended %d-remaning %d) chars at %d in '%s' (%d)\n", 
         nCharsToDelete, nIntendedChars, nChars, c.nOffset, 
         debugstr_w(run->strText->szData), run->strText->nLen);
 
       if (!c.nOffset && ME_StrVLen(run->strText) == nCharsToDelete)
       {
         /* undo = reinsert whole run */
         /* nOfs is a character offset (from the start of the document
            to the current (deleted) run */
         ME_UndoItem *pUndo = ME_AddUndoItem(editor, diUndoInsertRun, c.pRun);
         if (pUndo)
           pUndo->di.member.run.nCharOfs = nOfs;
       }
       else
       {
         /* undo = reinsert partial run */
         ME_UndoItem *pUndo = ME_AddUndoItem(editor, diUndoInsertRun, c.pRun);
         if (pUndo) {
           ME_DestroyString(pUndo->di.member.run.strText);
           pUndo->di.member.run.nCharOfs = nOfs;
           pUndo->di.member.run.strText = ME_MakeStringN(run->strText->szData+c.nOffset, nCharsToDelete);
         }
       }
       TRACE("Post deletion string: %s (%d)\n", debugstr_w(run->strText->szData), run->strText->nLen);
       TRACE("Shift value: %d\n", shift);
       ME_StrDeleteV(run->strText, c.nOffset, nCharsToDelete);
       
       /* update cursors (including c) */
       for (i=-1; i<editor->nCursors; i++) {
         ME_Cursor *pThisCur = editor->pCursors + i; 
         if (i == -1) pThisCur = &c;
         if (pThisCur->pRun == cursor.pRun) {
           if (pThisCur->nOffset > cursor.nOffset) {
             if (pThisCur->nOffset-cursor.nOffset < nCharsToDelete)
               pThisCur->nOffset = cursor.nOffset;
             else
               pThisCur->nOffset -= nCharsToDelete;
             assert(pThisCur->nOffset >= 0);
             assert(pThisCur->nOffset <= ME_StrVLen(run->strText));
           }
           if (pThisCur->nOffset == ME_StrVLen(run->strText))
           {
             pThisCur->pRun = ME_FindItemFwd(pThisCur->pRun, diRunOrParagraphOrEnd);
             assert(pThisCur->pRun->type == diRun);
             pThisCur->nOffset = 0;
           }
         }
       }
       
       /* c = updated data now */
       
       if (c.pRun == cursor.pRun)
         ME_SkipAndPropagateCharOffset(c.pRun, shift);
       else
         ME_PropagateCharOffset(c.pRun, shift);
 
       if (!ME_StrVLen(cursor.pRun->member.run.strText))
       {
         TRACE("Removing useless run\n");
         ME_Remove(cursor.pRun);
         ME_DestroyDisplayItem(cursor.pRun);
       }
       
       shift = 0;
       /*
       ME_CheckCharOffsets(editor);
       */
       continue;
     }
   }
 }
 
 void ME_DeleteTextAtCursor(ME_TextEditor *editor, int nCursor, 
   int nChars)
 {  
   assert(nCursor>=0 && nCursor<editor->nCursors);
   /* text operations set modified state */
   editor->nModifyStep = 1;
   ME_InternalDeleteText(editor, ME_GetCursorOfs(editor, nCursor), nChars);
 }
 
 static ME_DisplayItem *
 ME_InternalInsertTextFromCursor(ME_TextEditor *editor, int nCursor,
                                 const WCHAR *str, int len, ME_Style *style,
                                 int flags)
 {
   ME_Cursor *p = &editor->pCursors[nCursor];
 
   editor->bCaretAtEnd = FALSE;
   
   assert(p->pRun->type == diRun);
   
   return ME_InsertRunAtCursor(editor, p, style, str, len, flags);
 }
 
 
 void ME_InsertOLEFromCursor(ME_TextEditor *editor, const REOBJECT* reo, int nCursor)
 {
   ME_Style              *pStyle = ME_GetInsertStyle(editor, nCursor);
   ME_DisplayItem        *di;
   WCHAR                 space = ' ';
   
   /* FIXME no no no */
   if (ME_IsSelection(editor))
     ME_DeleteSelection(editor);
 
   di = ME_InternalInsertTextFromCursor(editor, nCursor, &space, 1, pStyle,
                                        MERF_GRAPHICS);
   di->member.run.ole_obj = ALLOC_OBJ(*reo);
   ME_CopyReObject(di->member.run.ole_obj, reo);
   ME_SendSelChange(editor);
 }
 
 
 void ME_InsertEndRowFromCursor(ME_TextEditor *editor, int nCursor)
 {
   ME_Style              *pStyle = ME_GetInsertStyle(editor, nCursor);
   ME_DisplayItem        *di;
   WCHAR                 space = ' ';
 
   /* FIXME no no no */
   if (ME_IsSelection(editor))
     ME_DeleteSelection(editor);
 
   di = ME_InternalInsertTextFromCursor(editor, nCursor, &space, 1, pStyle,
                                        MERF_ENDROW);
   ME_SendSelChange(editor);
 }
 
 void
 ME_InsertTableCellFromCursor(ME_TextEditor *editor, int nCursor)
 {
   WCHAR tab = '\t';
   ME_DisplayItem *p, *run;
   ME_Style *pStyle = ME_GetInsertStyle(editor, nCursor);
   
   p = ME_InternalInsertTextFromCursor(editor, nCursor, &tab, 1, pStyle,
                                       MERF_CELL);
   run = p;
   while ((run = ME_FindItemBack(run, diRunOrParagraph))->type == diRun)
   {
     if (run->member.run.nFlags & MERF_CELL)
     {
       assert(run->member.run.pCell->next);
       p->member.run.pCell = run->member.run.pCell->next;
       return;
     }
   }
   assert(run->type == diParagraph);
   assert(run->member.para.bTable);
   assert(run->member.para.pCells);
   p->member.run.pCell = run->member.para.pCells;
 }
 
 
 void ME_InsertTextFromCursor(ME_TextEditor *editor, int nCursor, 
   const WCHAR *str, int len, ME_Style *style)
 {
   const WCHAR *pos;
   ME_Cursor *p = NULL;
   int oldLen;
 
   /* FIXME really HERE ? */
   if (ME_IsSelection(editor))
     ME_DeleteSelection(editor);
 
   /* FIXME: is this too slow? */
   /* Didn't affect performance for WM_SETTEXT (around 50sec/30K) */
   oldLen = ME_GetTextLength(editor);
 
   /* text operations set modified state */
   editor->nModifyStep = 1;
 
   assert(style);
 
   assert(nCursor>=0 && nCursor<editor->nCursors);
   if (len == -1)
     len = lstrlenW(str);
 
   /* grow the text limit to fit our text */
   if(editor->nTextLimit < oldLen +len)
     editor->nTextLimit = oldLen + len;
 
   while (len)
   {
     pos = str;
     /* FIXME this sucks - no respect for unicode (what else can be a line separator in unicode?) */
     while(pos-str < len && *pos != '\r' && *pos != '\n' && *pos != '\t')
       pos++;
     if (pos-str < len && *pos == '\t') { /* handle tabs */
       WCHAR tab = '\t';
 
       if (pos!=str)
         ME_InternalInsertTextFromCursor(editor, nCursor, str, pos-str, style, 0);
     
       ME_InternalInsertTextFromCursor(editor, nCursor, &tab, 1, style, MERF_TAB);
  
       pos++;
       if(pos-str <= len) {
         len -= pos - str;
         str = pos;
         continue;
       }
     }
     /* handle special \r\r\n sequence (richedit 2.x and higher only) */
     if (!editor->bEmulateVersion10 && pos-str < len-2 && pos[0] == '\r' && pos[1] == '\r' && pos[2] == '\n') {
       WCHAR space = ' ';
 
       if (pos!=str)
         ME_InternalInsertTextFromCursor(editor, nCursor, str, pos-str, style, 0);
 
       ME_InternalInsertTextFromCursor(editor, nCursor, &space, 1, style, 0);
 
       pos+=3;
       if(pos-str <= len) {
         len -= pos - str;
         str = pos;
         continue;
       }
     }
     if (pos-str < len) {   /* handle EOLs */
       ME_DisplayItem *tp, *end_run;
       ME_Style *tmp_style;
       int numCR, numLF;
 
       if (pos!=str)
         ME_InternalInsertTextFromCursor(editor, nCursor, str, pos-str, style, 0);
       p = &editor->pCursors[nCursor];
       if (p->nOffset) {
         ME_SplitRunSimple(editor, p->pRun, p->nOffset);
         p = &editor->pCursors[nCursor];
       }
       tmp_style = ME_GetInsertStyle(editor, nCursor);
       /* ME_SplitParagraph increases style refcount */
 
       /* Encode and fill number of CR and LF according to emulation mode */
       if (editor->bEmulateVersion10) {
         const WCHAR * tpos;
 
         /* We have to find out how many consecutive \r are there, and if there
            is a \n terminating the run of \r's. */
         numCR = 0; numLF = 0;
         tpos = pos;
         while (tpos-str < len && *tpos == '\r') {
           tpos++;
           numCR++;
         }
         if (tpos-str >= len) {
           /* Reached end of text without finding anything but '\r' */
           if (tpos != pos) {
             pos++;
           }
           numCR = 1; numLF = 0;
         } else if (*tpos == '\n') {
           /* The entire run of \r's plus the one \n is one single line break */
           pos = tpos + 1;
           numLF = 1;
         } else {
           /* Found some other content past the run of \r's */
           pos++;
           numCR = 1; numLF = 0;
         }
       } else {
         if(pos-str < len && *pos =='\r')
           pos++;
         if(pos-str < len && *pos =='\n')
           pos++;
         numCR = 1; numLF = 0;
       }
       tp = ME_SplitParagraph(editor, p->pRun, p->pRun->member.run.style, numCR, numLF);
       p->pRun = ME_FindItemFwd(tp, diRun);
       end_run = ME_FindItemBack(tp, diRun);
       ME_ReleaseStyle(end_run->member.run.style);
       end_run->member.run.style = tmp_style;
       p->nOffset = 0;
 
       if(pos-str <= len) {
         len -= pos - str;
         str = pos;
         continue;
       }
     }
     ME_InternalInsertTextFromCursor(editor, nCursor, str, len, style, 0);
     len = 0;
   }
 }
 
 
 static BOOL
 ME_MoveCursorChars(ME_TextEditor *editor, ME_Cursor *pCursor, int nRelOfs)
 {
   ME_DisplayItem *pRun = pCursor->pRun;
   
   if (nRelOfs == -1)
   {
     if (!pCursor->nOffset)
     {
       do {
         pRun = ME_FindItemBack(pRun, diRunOrParagraph);
         assert(pRun);
         switch (pRun->type)
         {
           case diRun:
             break;
           case diParagraph:
             if (pRun->member.para.prev_para->type == diTextStart)
               return FALSE;
             pRun = ME_FindItemBack(pRun, diRunOrParagraph);
             /* every paragraph ought to have at least one run */
             assert(pRun && pRun->type == diRun);
             assert(pRun->member.run.nFlags & MERF_ENDPARA);
             break;
           default:
             assert(pRun->type != diRun && pRun->type != diParagraph);
             return FALSE;
         }
       } while (RUN_IS_HIDDEN(&pRun->member.run));
       pCursor->pRun = pRun;
       if (pRun->member.run.nFlags & MERF_ENDPARA)
         pCursor->nOffset = 0;
       else
         pCursor->nOffset = pRun->member.run.strText->nLen;
     }
     
     if (pCursor->nOffset)
       pCursor->nOffset = ME_StrRelPos2(pCursor->pRun->member.run.strText, pCursor->nOffset, nRelOfs);
     return TRUE;
   }
   else
   {
     if (!(pRun->member.run.nFlags & MERF_ENDPARA))
     {
       int new_ofs = ME_StrRelPos2(pRun->member.run.strText, pCursor->nOffset, nRelOfs);
     
       if (new_ofs < pRun->member.run.strText->nLen)
       {
         pCursor->nOffset = new_ofs;
         return TRUE;
       }
     }
     do {
       pRun = ME_FindItemFwd(pRun, diRun);
     } while (pRun && RUN_IS_HIDDEN(&pRun->member.run));
     if (pRun)
     {
       pCursor->pRun = pRun;
       pCursor->nOffset = 0;
       return TRUE;
     }
   }
   return FALSE;
 }
 
 
 static BOOL
 ME_MoveCursorWords(ME_TextEditor *editor, ME_Cursor *cursor, int nRelOfs)
 {
   ME_DisplayItem *pRun = cursor->pRun, *pOtherRun;
   int nOffset = cursor->nOffset;
   
   if (nRelOfs == -1)
   {
     /* Backward movement */
     while (TRUE)
     {
       nOffset = ME_CallWordBreakProc(editor, pRun->member.run.strText,
                                      nOffset, WB_MOVEWORDLEFT);
        if (nOffset)
         break;
       pOtherRun = ME_FindItemBack(pRun, diRunOrParagraph);
       if (pOtherRun->type == diRun)
       {
         if (ME_CallWordBreakProc(editor, pOtherRun->member.run.strText,
                                  pOtherRun->member.run.strText->nLen - 1,
                                  WB_ISDELIMITER)
             && !(pRun->member.run.nFlags & MERF_ENDPARA)
             && !(cursor->pRun == pRun && cursor->nOffset == 0)
             && !ME_CallWordBreakProc(editor, pRun->member.run.strText, 0,
                                      WB_ISDELIMITER))
           break;
         pRun = pOtherRun;
         nOffset = pOtherRun->member.run.strText->nLen;
       }
       else if (pOtherRun->type == diParagraph)
       {
         if (cursor->pRun == pRun && cursor->nOffset == 0)
         {
           /* Paragraph breaks are treated as separate words */
           if (pOtherRun->member.para.prev_para->type == diTextStart)
             return FALSE;
           pRun = ME_FindItemBack(pOtherRun, diRunOrParagraph);
         }
         break;
       }
     }
   }
   else
   {
     /* Forward movement */
     BOOL last_delim = FALSE;
     
     while (TRUE)
     {
       if (last_delim && !ME_CallWordBreakProc(editor, pRun->member.run.strText,
                                               nOffset, WB_ISDELIMITER))
         break;
       nOffset = ME_CallWordBreakProc(editor, pRun->member.run.strText,
                                      nOffset, WB_MOVEWORDRIGHT);
       if (nOffset < pRun->member.run.strText->nLen)
         break;
       pOtherRun = ME_FindItemFwd(pRun, diRunOrParagraphOrEnd);
       if (pOtherRun->type == diRun)
       {
         last_delim = ME_CallWordBreakProc(editor, pRun->member.run.strText,
                                           nOffset - 1, WB_ISDELIMITER);
         pRun = pOtherRun;
         nOffset = 0;
       }
       else if (pOtherRun->type == diParagraph)
       {
         if (cursor->pRun == pRun)
           pRun = ME_FindItemFwd(pOtherRun, diRun);
         nOffset = 0;
         break;
       }
       else /* diTextEnd */
       {
         if (cursor->pRun == pRun)
           return FALSE;
         nOffset = 0;
         break;
       }
     }
   }
   cursor->pRun = pRun;
   cursor->nOffset = nOffset;
   return TRUE;
 }
 
 
 void
 ME_SelectWord(ME_TextEditor *editor)
 {
   if (!(editor->pCursors[0].pRun->member.run.nFlags & MERF_ENDPARA))
     ME_MoveCursorWords(editor, &editor->pCursors[0], -1);
   ME_MoveCursorWords(editor, &editor->pCursors[1], +1);
   ME_InvalidateSelection(editor);
   ME_SendSelChange(editor);
 }
 
 
 int ME_GetCursorOfs(ME_TextEditor *editor, int nCursor)
 {
   ME_Cursor *pCursor = &editor->pCursors[nCursor];
   return ME_GetParagraph(pCursor->pRun)->member.para.nCharOfs
     + pCursor->pRun->member.run.nCharOfs + pCursor->nOffset;
 }
 
 static void ME_FindPixelPos(ME_TextEditor *editor, int x, int y, ME_Cursor *result, BOOL *is_eol)
 {
   ME_DisplayItem *p = editor->pBuffer->pFirst->member.para.next_para;
   ME_DisplayItem *last = NULL;
   int rx = 0;
 
   if (is_eol)
     *is_eol = 0;
 
   /* find paragraph */
   for (; p != editor->pBuffer->pLast; p = p->member.para.next_para)
   {
     assert(p->type == diParagraph);
     if (y < p->member.para.nYPos + p->member.para.nHeight)
     {
       y -= p->member.para.nYPos;
       p = ME_FindItemFwd(p, diStartRow);
       break;
     }
   }
   /* find row */
   for (; p != editor->pBuffer->pLast; )
   {
     ME_DisplayItem *pp;
     assert(p->type == diStartRow);
     if (y < p->member.row.nYPos + p->member.row.nHeight)
     {
         p = ME_FindItemFwd(p, diRun);
         break;
     }
     pp = ME_FindItemFwd(p, diStartRowOrParagraphOrEnd);
     if (pp->type != diStartRow)
     {
         p = ME_FindItemFwd(p, diRun);
         break;
     }
     p = pp;
   }
   for (; p != editor->pBuffer->pLast; p = p->next)
   {
     switch (p->type)
     {
     case diRun:
       rx = x - p->member.run.pt.x;
       if (rx < p->member.run.nWidth)
       {
       found_here:
         assert(p->type == diRun);
         if ((p->member.run.nFlags & MERF_ENDPARA) || rx < 0)
           rx = 0;
         result->pRun = p;
         result->nOffset = ME_CharFromPointCursor(editor, rx, &p->member.run);
         if (editor->pCursors[0].nOffset == p->member.run.strText->nLen && rx)
         {
           result->pRun = ME_FindItemFwd(editor->pCursors[0].pRun, diRun);
           result->nOffset = 0;
         }
         return;
       }
       break;
     case diStartRow:
       p = ME_FindItemFwd(p, diRun);
       if (is_eol) *is_eol = 1;
       rx = 0; /* FIXME not sure */
       goto found_here;
     case diParagraph:
     case diTextEnd:
       rx = 0; /* FIXME not sure */
       p = last;
       goto found_here;
     default: assert(0);
     }
     last = p;
   }
   result->pRun = ME_FindItemBack(p, diRun);
   result->nOffset = 0;
   assert(result->pRun->member.run.nFlags & MERF_ENDPARA);
 }
 
 
 int
 ME_CharFromPos(ME_TextEditor *editor, int x, int y)
 {
   ME_Cursor cursor;
   RECT rc;
 
   GetClientRect(editor->hWnd, &rc);
   if (x < 0 || y < 0 || x >= rc.right || y >= rc.bottom)
     return -1;
   y += ME_GetYScrollPos(editor);
   ME_FindPixelPos(editor, x, y, &cursor, NULL);
   return (ME_GetParagraph(cursor.pRun)->member.para.nCharOfs
           + cursor.pRun->member.run.nCharOfs + cursor.nOffset);
 }
 
 
 void ME_LButtonDown(ME_TextEditor *editor, int x, int y)
 {
   ME_Cursor tmp_cursor;
   int is_selection = 0;
   
   editor->nUDArrowX = -1;
   
   y += ME_GetYScrollPos(editor);
 
   tmp_cursor = editor->pCursors[0];
   is_selection = ME_IsSelection(editor);
 
   if (x >= editor->selofs)
   {
     ME_FindPixelPos(editor, x, y, &editor->pCursors[0], &editor->bCaretAtEnd);
     if (GetKeyState(VK_SHIFT)>=0)
     {
       editor->pCursors[1] = editor->pCursors[0];
     }
     else if (!is_selection) {
       editor->pCursors[1] = tmp_cursor;
       is_selection = 1;
     }
 
     ME_InvalidateSelection(editor);
     HideCaret(editor->hWnd);
     ME_MoveCaret(editor);
     ShowCaret(editor->hWnd);
     ME_ClearTempStyle(editor);
     ME_SendSelChange(editor);
   }
   else
   {
     ME_DisplayItem *pRow;
 
     editor->linesel = 1;
     editor->sely = y;
     /* Set pCursors[0] to beginning of line */
     ME_FindPixelPos(editor, x, y, &editor->pCursors[1], &editor->bCaretAtEnd);
     /* Set pCursors[1] to end of line */
     pRow = ME_FindItemFwd(editor->pCursors[1].pRun, diStartRowOrParagraphOrEnd);
     assert(pRow);
     /* pCursor[0] is the position where the cursor will be drawn,
      * pCursor[1] is the other end of the selection range
      * pCursor[2] and [3] are backups of [0] and [1] so I
      * don't have to look them up again
      */
 
     if (pRow->type == diStartRow) {
       /* FIXME WTF was I thinking about here ? */
       ME_DisplayItem *pRun = ME_FindItemFwd(pRow, diRun);
       assert(pRun);
       editor->pCursors[0].pRun = pRun;
       editor->pCursors[0].nOffset = 0;
       editor->bCaretAtEnd = 1;
     } else {
       editor->pCursors[0].pRun = ME_FindItemBack(pRow, diRun);
       assert(editor->pCursors[0].pRun && editor->pCursors[0].pRun->member.run.nFlags & MERF_ENDPARA);
       editor->pCursors[0].nOffset = 0;
       editor->bCaretAtEnd = 0;
     }
     editor->pCursors[2] = editor->pCursors[0];
     editor->pCursors[3] = editor->pCursors[1];
     ME_InvalidateSelection(editor);
     HideCaret(editor->hWnd);
     ME_MoveCaret(editor);
     ShowCaret(editor->hWnd);
     ME_ClearTempStyle(editor);
     ME_SendSelChange(editor);
   }
 }
 
 void ME_MouseMove(ME_TextEditor *editor, int x, int y)
 {
   ME_Cursor tmp_cursor;
   
   y += ME_GetYScrollPos(editor);
 
   tmp_cursor = editor->pCursors[0];
   /* FIXME: do something with the return value of ME_FindPixelPos */
   if (!editor->linesel)
     ME_FindPixelPos(editor, x, y, &tmp_cursor, &editor->bCaretAtEnd);
   else ME_FindPixelPos(editor, (y > editor->sely) * editor->rcFormat.right, y, &tmp_cursor, &editor->bCaretAtEnd);
 
   if (!memcmp(&tmp_cursor, editor->pCursors, sizeof(tmp_cursor)))
     return;
 
   ME_InvalidateSelection(editor);
   if (!editor->linesel)
     editor->pCursors[0] = tmp_cursor;
   else if (!memcmp(&tmp_cursor, editor->pCursors+2, sizeof(tmp_cursor)) ||
            !memcmp(&tmp_cursor, editor->pCursors+3, sizeof(tmp_cursor)))
   {
     editor->pCursors[0] = editor->pCursors[2];
     editor->pCursors[1] = editor->pCursors[3];
   }
   else if (y < editor->sely)
   {
     editor->pCursors[0] = tmp_cursor;
     editor->pCursors[1] = editor->pCursors[2];
   }
   else
   {
     editor->pCursors[0] = tmp_cursor;
     editor->pCursors[1] = editor->pCursors[3];
   }
 
   HideCaret(editor->hWnd);
   ME_MoveCaret(editor);
   ME_InvalidateSelection(editor);
   ShowCaret(editor->hWnd);
   ME_SendSelChange(editor);
   SendMessageW(editor->hWnd, EM_SCROLLCARET, 0, 0);
 }
 
 static ME_DisplayItem *ME_FindRunInRow(ME_TextEditor *editor, ME_DisplayItem *pRow, 
                                 int x, int *pOffset, int *pbCaretAtEnd)
 {
   ME_DisplayItem *pNext, *pLastRun;
   pNext = ME_FindItemFwd(pRow, diRunOrStartRow);
   assert(pNext->type == diRun);
   pLastRun = pNext;
   if (pbCaretAtEnd) *pbCaretAtEnd = FALSE;
   if (pOffset) *pOffset = 0;
   do {
     int run_x = pNext->member.run.pt.x;
     int width = pNext->member.run.nWidth;
     if (x < run_x)
     {
       return pNext;
     }
     if (x >= run_x && x < run_x+width)
     {
       int ch = ME_CharFromPointCursor(editor, x-run_x, &pNext->member.run);
       ME_String *s = pNext->member.run.strText;
       if (ch < s->nLen) {
         if (pOffset)
           *pOffset = ch;
         return pNext;          
       }
     }
     pLastRun = pNext;
     pNext = ME_FindItemFwd(pNext, diRunOrStartRow);
   } while(pNext && pNext->type == diRun);
   
   if ((pLastRun->member.run.nFlags & MERF_ENDPARA) == 0)
   {
     pNext = ME_FindItemFwd(pNext, diRun);
     if (pbCaretAtEnd) *pbCaretAtEnd = TRUE;
     return pNext;
   } else {
     return pLastRun;
   }
 }
 
 static int ME_GetXForArrow(ME_TextEditor *editor, ME_Cursor *pCursor)
 {
   ME_DisplayItem *pRun = pCursor->pRun;
   int x;
 
   if (editor->nUDArrowX != -1)
     x = editor->nUDArrowX;
   else {
     if (editor->bCaretAtEnd)
     {
       pRun = ME_FindItemBack(pRun, diRun);
       assert(pRun);
       x = pRun->member.run.pt.x + pRun->member.run.nWidth;
     }
     else {
       x = pRun->member.run.pt.x;
       x += ME_PointFromChar(editor, &pRun->member.run, pCursor->nOffset);
     }
     editor->nUDArrowX = x;
   }
   return x;
 }
 
 
 static void
 ME_MoveCursorLines(ME_TextEditor *editor, ME_Cursor *pCursor, int nRelOfs)
 {
   ME_DisplayItem *pRun = pCursor->pRun;
   ME_DisplayItem *pItem;
   int x = ME_GetXForArrow(editor, pCursor);
 
   if (editor->bCaretAtEnd && !pCursor->nOffset)
     pRun = ME_FindItemBack(pRun, diRun);
   if (!pRun)
     return;
   if (nRelOfs == -1)
   {
     /* start of this row */
     pItem = ME_FindItemBack(pRun, diStartRow);
     assert(pItem);
     /* start of the previous row */
     pItem = ME_FindItemBack(pItem, diStartRow);
   }
   else
   {
     /* start of the next row */
     pItem = ME_FindItemFwd(pRun, diStartRow);
     /* FIXME If diParagraph is before diStartRow, wrap the next paragraph?
     */
   }
   if (!pItem)
   {
     /* row not found - ignore */
     return;
   }
   pCursor->pRun = ME_FindRunInRow(editor, pItem, x, &pCursor->nOffset, &editor->bCaretAtEnd);
   assert(pCursor->pRun);
   assert(pCursor->pRun->type == diRun);
 }
 
 
 static void ME_ArrowPageUp(ME_TextEditor *editor, ME_Cursor *pCursor)
 {
   ME_DisplayItem *pRun = pCursor->pRun;
   ME_DisplayItem *pLast, *p;
   int x, y, ys, yd, yp, yprev;
   ME_Cursor tmp_curs = *pCursor;
   
   x = ME_GetXForArrow(editor, pCursor);
   if (!pCursor->nOffset && editor->bCaretAtEnd)
     pRun = ME_FindItemBack(pRun, diRun);
   
   p = ME_FindItemBack(pRun, diStartRowOrParagraph);
   assert(p->type == diStartRow);
   yp = ME_FindItemBack(p, diParagraph)->member.para.nYPos;
   yprev = ys = y = yp + p->member.row.nYPos;
   yd = y - editor->sizeWindow.cy;
   pLast = p;
   
   do {
     p = ME_FindItemBack(p, diStartRowOrParagraph);
     if (!p)
       break;
     if (p->type == diParagraph) { /* crossing paragraphs */
       if (p->member.para.prev_para == NULL)
         break;
       yp = p->member.para.prev_para->member.para.nYPos;
       continue;
     }
     y = yp + p->member.row.nYPos;
     if (y < yd)
       break;
     pLast = p;
     yprev = y;
   } while(1);
   
   pCursor->pRun = ME_FindRunInRow(editor, pLast, x, &pCursor->nOffset, &editor->bCaretAtEnd);
   ME_UpdateSelection(editor, &tmp_curs);
   if (yprev < editor->sizeWindow.cy)
   {
     ME_EnsureVisible(editor, ME_FindItemFwd(editor->pBuffer->pFirst, diRun));
     ME_Repaint(editor);
   }
   else 
   {
     ME_ScrollUp(editor, ys-yprev);
   }
   assert(pCursor->pRun);
   assert(pCursor->pRun->type == diRun);
 }
 
 /* FIXME: in the original RICHEDIT, PageDown always scrolls by the same amount 
    of pixels, even if it makes the scroll bar position exceed its normal maximum.
    In such a situation, clicking the scrollbar restores its position back to the
    normal range (ie. sets it to (doclength-screenheight)). */
 
 static void ME_ArrowPageDown(ME_TextEditor *editor, ME_Cursor *pCursor)
 {
   ME_DisplayItem *pRun = pCursor->pRun;
   ME_DisplayItem *pLast, *p;
   int x, y, ys, yd, yp, yprev;
   ME_Cursor tmp_curs = *pCursor;
   
   x = ME_GetXForArrow(editor, pCursor);
   if (!pCursor->nOffset && editor->bCaretAtEnd)
     pRun = ME_FindItemBack(pRun, diRun);
   
   p = ME_FindItemBack(pRun, diStartRowOrParagraph);
   assert(p->type == diStartRow);
   yp = ME_FindItemBack(p, diParagraph)->member.para.nYPos;
   yprev = ys = y = yp + p->member.row.nYPos;
   yd = y + editor->sizeWindow.cy;
   pLast = p;
   
   do {
     p = ME_FindItemFwd(p, diStartRowOrParagraph);
     if (!p)
       break;
     if (p->type == diParagraph) {
       yp = p->member.para.nYPos;
       continue;
     }
     y = yp + p->member.row.nYPos;
     if (y >= yd)
       break;
     pLast = p;
     yprev = y;
   } while(1);
   
   pCursor->pRun = ME_FindRunInRow(editor, pLast, x, &pCursor->nOffset, &editor->bCaretAtEnd);
   ME_UpdateSelection(editor, &tmp_curs);
   if (yprev >= editor->nTotalLength-editor->sizeWindow.cy)
   {
     ME_EnsureVisible(editor, ME_FindItemBack(editor->pBuffer->pLast, diRun));
     ME_Repaint(editor);
   }
   else 
   {
     ME_ScrollUp(editor,ys-yprev);
   }
   assert(pCursor->pRun);
   assert(pCursor->pRun->type == diRun);
 }
 
 static void ME_ArrowHome(ME_TextEditor *editor, ME_Cursor *pCursor)
 {
   ME_DisplayItem *pRow = ME_FindItemBack(pCursor->pRun, diStartRow);
   ME_WrapMarkedParagraphs(editor);
   if (pRow) {
     ME_DisplayItem *pRun;
     if (editor->bCaretAtEnd && !pCursor->nOffset) {
       pRow = ME_FindItemBack(pRow, diStartRow);
       if (!pRow)
         return;
     }
     pRun = ME_FindItemFwd(pRow, diRun);
     if (pRun) {
       pCursor->pRun = pRun;
       pCursor->nOffset = 0;
     }
   }
   editor->bCaretAtEnd = FALSE;
 }
 
 static void ME_ArrowCtrlHome(ME_TextEditor *editor, ME_Cursor *pCursor)
 {
   ME_DisplayItem *pRow = ME_FindItemBack(pCursor->pRun, diTextStart);
   if (pRow) {
     ME_DisplayItem *pRun = ME_FindItemFwd(pRow, diRun);
     if (pRun) {
       pCursor->pRun = pRun;
       pCursor->nOffset = 0;
     }
   }
 }
 
 static void ME_ArrowEnd(ME_TextEditor *editor, ME_Cursor *pCursor)
 {
   ME_DisplayItem *pRow;
   
   if (editor->bCaretAtEnd && !pCursor->nOffset)
     return;
   
   pRow = ME_FindItemFwd(pCursor->pRun, diStartRowOrParagraphOrEnd);
   assert(pRow);
   if (pRow->type == diStartRow) {
     /* FIXME WTF was I thinking about here ? */
     ME_DisplayItem *pRun = ME_FindItemFwd(pRow, diRun);
     assert(pRun);
     pCursor->pRun = pRun;
     pCursor->nOffset = 0;
     editor->bCaretAtEnd = 1;
     return;
   }
   pCursor->pRun = ME_FindItemBack(pRow, diRun);
   assert(pCursor->pRun && pCursor->pRun->member.run.nFlags & MERF_ENDPARA);
   pCursor->nOffset = 0;
   editor->bCaretAtEnd = FALSE;
 }
       
 static void ME_ArrowCtrlEnd(ME_TextEditor *editor, ME_Cursor *pCursor)
 {
   ME_DisplayItem *p = ME_FindItemFwd(pCursor->pRun, diTextEnd);
   assert(p);
   p = ME_FindItemBack(p, diRun);
   assert(p);
   assert(p->member.run.nFlags & MERF_ENDPARA);
   pCursor->pRun = p;
   pCursor->nOffset = 0;
   editor->bCaretAtEnd = FALSE;
 }
 
 BOOL ME_IsSelection(ME_TextEditor *editor)
 {
   return memcmp(&editor->pCursors[0], &editor->pCursors[1], sizeof(ME_Cursor))!=0;
 }
 
 static int ME_GetSelCursor(ME_TextEditor *editor, int dir)
 {
   int cdir = ME_GetCursorOfs(editor, 0) - ME_GetCursorOfs(editor, 1);
   
   if (cdir*dir>0)
     return 0;
   else
     return 1;
 }
 
 BOOL ME_UpdateSelection(ME_TextEditor *editor, const ME_Cursor *pTempCursor)
 {
   ME_Cursor old_anchor = editor->pCursors[1];
   
   if (GetKeyState(VK_SHIFT)>=0) /* cancelling selection */
   {
     /* any selection was present ? if so, it's no more, repaint ! */
     editor->pCursors[1] = editor->pCursors[0];
     if (memcmp(pTempCursor, &old_anchor, sizeof(ME_Cursor))) {
       return TRUE;
     }
     return FALSE;
   }
   else
   {
     if (!memcmp(pTempCursor, &editor->pCursors[1], sizeof(ME_Cursor))) /* starting selection */
     {
       editor->pCursors[1] = *pTempCursor;
       return TRUE;
     }
   }
 
   ME_Repaint(editor);
   return TRUE;
 }
 
 void ME_DeleteSelection(ME_TextEditor *editor)
 {
   int from, to;
   ME_GetSelection(editor, &from, &to);
   ME_DeleteTextAtCursor(editor, ME_GetSelCursor(editor,-1), to-from);
 }
 
 ME_Style *ME_GetSelectionInsertStyle(ME_TextEditor *editor)
 {
   return ME_GetInsertStyle(editor, 0);
 }
 
 void ME_SendSelChange(ME_TextEditor *editor)
 {
   SELCHANGE sc;
 
   if (!(editor->nEventMask & ENM_SELCHANGE))
     return;
   
   sc.nmhdr.hwndFrom = editor->hWnd;
   sc.nmhdr.idFrom = GetWindowLongW(editor->hWnd, GWLP_ID);
   sc.nmhdr.code = EN_SELCHANGE;
   SendMessageW(editor->hWnd, EM_EXGETSEL, 0, (LPARAM)&sc.chrg);
   sc.seltyp = SEL_EMPTY;
   if (sc.chrg.cpMin != sc.chrg.cpMax)
     sc.seltyp |= SEL_TEXT;
   if (sc.chrg.cpMin < sc.chrg.cpMax+1) /* wth were RICHEDIT authors thinking ? */
     sc.seltyp |= SEL_MULTICHAR;
   TRACE("cpMin=%d cpMax=%d seltyp=%d (%s %s)\n",
     sc.chrg.cpMin, sc.chrg.cpMax, sc.seltyp,
     (sc.seltyp & SEL_TEXT) ? "SEL_TEXT" : "",
     (sc.seltyp & SEL_MULTICHAR) ? "SEL_MULTICHAR" : "");
   if (sc.chrg.cpMin != editor->notified_cr.cpMin || sc.chrg.cpMax != editor->notified_cr.cpMax)
   {
     ME_ClearTempStyle(editor);
 
     editor->notified_cr = sc.chrg;
     SendMessageW(GetParent(editor->hWnd), WM_NOTIFY, sc.nmhdr.idFrom, (LPARAM)&sc);
   }
 }
 
 BOOL
 ME_ArrowKey(ME_TextEditor *editor, int nVKey, BOOL extend, BOOL ctrl)
 {
   int nCursor = 0;
   ME_Cursor *p = &editor->pCursors[nCursor];
   ME_Cursor tmp_curs = *p;
   BOOL success = FALSE;
   
   ME_CheckCharOffsets(editor);
   editor->nUDArrowX = -1;
   switch(nVKey) {
     case VK_LEFT:
       editor->bCaretAtEnd = 0;
       if (ctrl)
         success = ME_MoveCursorWords(editor, &tmp_curs, -1);
       else
         success = ME_MoveCursorChars(editor, &tmp_curs, -1);
       break;
     case VK_RIGHT:
       editor->bCaretAtEnd = 0;
       if (ctrl)
         success = ME_MoveCursorWords(editor, &tmp_curs, +1);
       else
         success = ME_MoveCursorChars(editor, &tmp_curs, +1);
       break;
     case VK_UP:
       ME_MoveCursorLines(editor, &tmp_curs, -1);
       break;
     case VK_DOWN:
       ME_MoveCursorLines(editor, &tmp_curs, +1);
       break;
     case VK_PRIOR:
       ME_ArrowPageUp(editor, &tmp_curs);
       break;
     case VK_NEXT:
       ME_ArrowPageDown(editor, &tmp_curs);
       break;
     case VK_HOME: {
       if (ctrl)
         ME_ArrowCtrlHome(editor, &tmp_curs);
       else
         ME_ArrowHome(editor, &tmp_curs);
       editor->bCaretAtEnd = 0;
       break;
     }
     case VK_END: 
       if (ctrl)
         ME_ArrowCtrlEnd(editor, &tmp_curs);
       else
         ME_ArrowEnd(editor, &tmp_curs);
       break;
   }
   
   if (!extend)
     editor->pCursors[1] = tmp_curs;
   *p = tmp_curs;
   
   ME_InvalidateSelection(editor);
   ME_Repaint(editor);
   HideCaret(editor->hWnd);
   ME_EnsureVisible(editor, tmp_curs.pRun); 
   ME_ShowCaret(editor);
   ME_SendSelChange(editor);
   return success;
 }